Fuel injection system



Nov. 1, 1960 T. M. BALL FUEL INJECTION SYSTEM Filed Sept. 3, 1959 2Sheets-Sheet 1 Nov. 1, 1960 T. M. BALL 2,958,320

FUEL INJECTION SYSTEM Filed Sept. 3, 1959 2 Sheets-Sheet 2 INVENTOR-7/3077746' MBd/Z BY AZ W FM United States Patent FUEL INJECTION SYSTEMThomas M. Ball, Bloomfield Hills, Mich, assignor to 'ChryslerCorporation, Highland Park, Mich, a corporation of Delaware Filed Sept.3, 1959, Ser. No. 837,963

16 Claims. (Cl. 123-119) This invention relates to a fuel injectionsystem particularly suited for use in an automotive internal combustionengine.

An object of the present invention is to provide an improved fuelinjection system of the above type wherein pressurized fuel from a fuelpump is supplied by a fuel feed conduit to the engine through fuelmetering means operable in response to variations in engine speed andload. A pressure regulating valve in the fuel conduit and responsive tothe pressure therein at opposite sides of the fuel metering meansmaintains a comparatively high predetermined minimum pressuredifferential across the metering means to minimize vapor formationtherein and to assure its reliable operation regardless of variations infuel pressure resulting from changes in speed, load, inertial effects,vehicle inclination, and the like. In consequence, the tolerances forthe fuel pump as well as for the dimensions of the conduit system can berelaxed ma terially with resulting cost savings and without affectingcritical pressure relation across the metering means.

Another object is to provide such a fuel injection system having apressure exerting means operable during engine acceleration, as forexample, an accelerator pump which can be linked with the customaryaccelerator pedal and personally actuated to inject a burst ofpressurized fuel into the feed conduit at a location downstream of themetering means for accelerating the engine, and to provide an operableconnection between the accelerator pump and the fuel metering means toaugment operation of the latter to increase the fuel flow to the engine.

In a type of fuel injection system with which the present invention isparticularly adapted, the fuel metering means includes a housingpartitioned by a movable wall into a first fuel pressure chamber and asecond or fuel pressure balancing chamber. The first chamber comprisespart of the feed conduit and has an orifice therein associated withvalve means adjustable to vary the orifice and thereby to control thefuel flow to the engine. The movable wall is operably connected with thevalve means and with a sensor device responsive to an engine operatingcondition and is shiftable to adjust the valve means in accordance withthe balance of forces elfected by the sensor device and the pressuredifferential between the two chambers.

A pressure equalizing duct in communication with the pressure balancingchamber and the feed conduit at a lo cation downstream of the meteringmeans maintains the same pressure differential between the first chamberand said downstream location that exists across the movable Wall. In theevent of sudden opening of the engine throttle for the purpose ofincreasing the fuel supply to the engine with such a system, a suddenoutflow of fuel from the first chamber results in a momentary change inthe forces on the movable wall causing the latter to move in a directionto decrease the volume of the first chamber and to increase the volumeof the second chamber. In consequence, without provision to thecontrary, fuel is robbed from the feed conduit via the equalizing ductin order to fill the increased volume of the second chamber.

This causes momentary leanness of the fuel-air mixture duringacceleration.

Another object of the invention is accordingly to provide simpleimproved means for preventing such an 0ccurrence as for example, anoperable mechanical or pressure actuated connection between the engineaccelerator mechanism and a portion of said valve means to vary saidorifice and augment said movable wall in increasing fuel flow to theengine without necessitating movement of the wall.

Another and more particular object is to provide a shiftable pressureactuated valve seat for said orifice cooperable with a valve element onsaid movable wall to vary said orifice and to provide a fluid connectionbetween the pressurized fuel of the accelerator pump and said valve seatto adjust the position of the latter with respect to said movable wallto prevent robbing of fuel from the feed conduit during suddenacceleration to the engine; to provide a one-way check valve in saidfluid connection to prevent a reverse fluid flow toward the acceleratorpump when the latter is not supplying pressurized fuel to said movableportion; and to provide resilient means normally holding the check valveclosed and being yieldable to open the check valve for passage of fluidin said fluid connection when the accelerator pump pressure exceeds apredetermined minimum.

Another object is to provide such a structure wherein said pressureregulating valve is applied to vary the restriction in said feed conduitat a point downstream of the aforesaid location associated with saidpressure equalizing duct.

Other objects are to provide a branch of said fluid connection openinginto said feed conduit at a location down stream of said pressureregulating valve means to supply acceleration fuel to said engine and toprovide a one-way check valve in said branch to prevent a reverse fuelflow from said feed conduit to said accelerator pump, the check valvemeans being yieldably urged to a closed position and being responsive tothe accelerator pump output pressure to open when the latter pressureexceeds a predetermined minimum value.

Another object is to provide an improved fuel injection system havingthe shiftable pressure actuated valve seat for said orifice cooperablewith the valve element on the movable wall to control the fuel flow tothe engine as aforesaid, the shiftable valve seat being quicklyresponsive to a comparatively small displacement of low pressure fluidand being thereby effectively operative with minimum interruption to thedesired pressure balance in the fuel metering system. Thus a fluidpressure pump of nominal size and output only is required for actuationof the shiftable valve seat, so that a portion of the output of aconventional fuel acceleration pump can be feasibly diverted to theshiftable valve seat to actuate the latter.

Other objects of this invention will appear in the following descriptionand appended claims, reference being had to the accompanying drawingsforming a part of this specification wherein like reference charactersdesignate corresponding parts in the several views.

Figure 1 is a fragmentary schematic sectional vew of a fuel injectionsystem embodying the present invention.

Figure 2 is an enlarged fragmentary view of the valve and shiftablevalve seat of Figure 1.

Figure 3 is a view similar to Figure 1, showing a modifled form of theinvention.

Figure 4 is a view similar to Figure 1, showing still anothermodification of the invention.

It is to be understood that the invention is not limited in itsapplication to the details of construction and arrangement of partsillustrated in the accompanying drawings, since the invention is capableof other embodiments and of being practiced or carried out in variousways.

Also it is to be understood that the phraseology or terminology employedherein is for the purpose of description and not of limitation.

- Referring to Figure l, a fuel injection system is shown comprisingseparate cylinder banks 10, air intake manifold conduits 11, exhaustconduits 12, and exhaust manifolds 13. The system comprises a fuelsupply tank 14, an engine operated speed sensor 15, an engine loadsensor 16, an accelerator pump 17, and fuel injection nozzles 18. Thespeed sensor is provided with four housing portions separated from eachother by diaphragms 23, 24, and 25 to provide four chambers 26, 27, 23,and 29. Chamber 26 communicates with fuel tank 14 through conduit 30 andby means of fuel pump 31 submerged in tank 14 is supplied with fuel inadequate volume and pressure to exceed the maximum requirements of theengine regardless of the engine load or speed. A tubular return flowmetering orifice member 32 as described below connects chamber 26 with areturn flow conduit 33 which extends to fuel tank 14 to return excessfuel thereto. A shiftable rod 19 having at one end a flattened returnvalve element 35 registering with the upstream side of orifice member 32is secured to each of the diaphragms 23, 24, and 25 by suitable grommets34.

A flyweight support 36 pivotally supports flyweights 37 at 38 and issecured to a flexible shaft 39 operatively connected to the engine torotate at a speed directly proportional to engine speed. The fiyweights37 have projections 26 which abut an end portion of rod 19 when theflyweights pivot outwardly in response to rotation of shaft 39, therebyto urge valve element 35 toward orifice member 32 against the oppositeforce of the fuel pressure in chamber 26 applied to diaphragm 23. Thusas engine speed increases or decreases respectively, valve element 35 ismoved toward or away from metering orifice member 32 to restrict orreduce the restriction at the latters opening.

Although the present invention is illustrated herein by way of examplewith a return flow type fuel injection system, it will be apparent fromthe following that the invention has application with other than returnflow systems, as for example wherein orifice member 32 is closed andvalve 35 is applied to conduit 30 to restrict the fuel flow therethroughwith increasing pressure in chamber 26; or wherein conduit 36 is closedand the fuel is pumped in a reverse direction through conduit 33 intochamber 26, and valve 35 is applied to restrict orifice member 32 withincreasing pressure in chamber 26.

Chamber 26 is connected with a downstream chamber 40 via load meteringorifice 41 and thence with a downstream fuel distribution chamber orrosette 42 via fuel supply conduits 43 and 44 in series. A load meteringneedle 45 extends through orifice 41 and terminates in a 'reverselytapered end portion 46 registering with the upstream side of orifice 41.Needle 45 is operatively connected to a piston 47 reciprocable incylinder 48, which n turn is connected with a low pressure portion ofeach intake manifold 11 of said engine by conduit 49. Low pressuretransmitted through conduit 49 causes piston 47 to move upwardly againstthe force of spring 50 and to urge the tapered valve 46 into closerproximity with the sides of orifice 41 to progressively restrict thelatter. Conversely, with increasing pressure in the intake manifolds, asfor example with increasing load, spring 50 urges piston 46 downwardlyto increase the opening of orifice 41. Vent duct 49a in the lowerportion of cylinder 48 maintams the space below piston 47 at atmosphericpressure.

A separate nozzle feed conduit 51 extends from chamber 42 to each of thefuel injection nozzles 18 located downstream of the throttle valve 52 inthe air intake manifold 53. Chamber 44) is also connected to chamber 27of the speed sensor unit by a pressure equalizing conduit 54 to providean adjustment of the fuel pressure differential across the meteringorifice 41, as explained below.

An idle boost conduit 55 communicates With m n 53 at a point adjacentthe edge of throttle valve 52 and with the chamber 28 of the speedsensor unit in order to augment operation of the flyweights 37 urgingrightward movement of valve element 35 when the engine is operated atlow speed and light load. By virtue of duct 55, the pressure in chamber28 during such conditions is lower than in chamber 29 which is vented tothe atmosphere by vent 56. The pressure in chamber 29 thus urges valveelement 35 toward orifice member 32 to retard the flow of return fueltherethrough and provide an enrichment of the engine fuel supply. Duringhigh speed or high load operation, the pressure differential acrossdiaphragm 25 has no appreciable effect.

The accelerator pump 17 has an inlet duct 57 in communication withreturn flow conduit 33 via ball check valve 53 and receives fuel intothe lower portion of cylinder 59 upon upward movement of the acceleratorpiston 60. In the present instance, piston 60 is connected in accordancewith customary practice with the personally operated accceleratorlinkage 60a. The latter is suitably connected with throttle valve 52 andnormally maintains piston 60 in an elevated position against the tensionof spring 60b when throttle valve 52 is closed. Upon opening of valve 52by operation of the throttle linkage, as for example during accelerationor increasing engine load, linkage 60a releases piston 60' for downwardmovement. The compressed spring 60b then moves piston 60 downwardly in apumping stroke to discharge pressurized fuel from cylinder 59. Uponactuation of throttle linkage 60a to close valve 52, piston 60 is raisedin an intake stroke against the force of spring 60b. Fuel is then drawninto the lower part of chamber 59 below piston 60 via duct 57. Bleedduct 61 connects cylinder 59 above piston 60 with return conduit 33 tofacilitate operation of piston 60 and to prevent entrapment of fuel inthe upper portion of cylinder 59. Restricted bleed duct 61ainterconnects duct 61 and the interior of cylinder 59 as describedbelow. 1

The pressurized fuel discharged from cylinder 59 upon the spring urgeddownward movement of piston 60 is directed through conduit 62 to conduit63 which extends through an enlarged portion 64 of the speed sensorhousing 15 at the left end of conduit 33. Conduit 33 opens to the leftinto a chamber or cavity 65 formed in housing portion 64. The cavity 65in turn enlarges leftward at 66. A tubular adaptor 67 having a threadedright end portion screws snugly into cavity 65 and enlarges radially at68 within the cavity 66. An O-ring type seal 69 provides a peripheralfluid seal between juxtaposed portions of the enlarged portions 64 and68 adjacent the outer periphery of the latter. Similarly a sealinggasket 70 provides a fluid seal between juxtaposed portions of theenlargements 64 and 68 around the outer periphery of the threadedportion of the adaptor 67.

As illustrated in Figure 2, the orifice member 32 comprises a shorttubular element freely slidable axially in the bore of tubular adaptor67 and opening into the cavity 65 which in turn opens into conduit 33. Aflexible annular diaphragm 72 extends coaxially around the member 32 andis retained in fluid sealing engagement against an annular movementlimiting shoulder 71 thereof by an annular retainer 73 which is eithersnugly pressed or screwed into position around member 32. The outerperiphery of diaphragm72 similarly seats in fluid sealing engagementagainst an annular shoulder of enlargement 68 and is secured in positionby a second annular retainer 74 snugly pressed or screwed into theopening of enlargement 68. The outer periphery of retainer 74 snuglyengages the inner periphery of enlargement 68 so as to move therewith asan integral unit. The inner periphery of retainer.7 4 is in free slidingengagement with tubular orifice member 32, sothat the latter is free forlimited leftward movement from the position shown in Figures 1 and 2,

One or more conduits 75 extending axially through enlargement 68 at theright side of diaphragm 72 provides communication between the latter andconduit 63 which extends through housing portion 64. A number of radialbores 76 in orifice member 32 provides communication between theinterior of the latter and the left side of diaphragm 72. In consequenceof the close sliding fit between the inner periphery of retainer 74 andorifice member 32, the pressure at the left of diaphragm 72 will beapproximately the same as the return flow pressure in line 33. Thusdiaphragm 72 will be readily responsive to any pressure at its rightside in excess of the return flow pressure to be shifted leftwardthereby, as explained below.

It is apparent that when accelerator piston 60 is depressed to dischargefuel from cylinder 59 during an accelerating operation, the fuelpressure discharged from cylinder 59 is directed through conduits 62,63, and 75 to the right side of diaphragm 72, thereby to move the latterand the freely shiftable orifice member 32 leftward toward valve element35. In consequence, orifice member 32 is restricted during the initialperiod of acceleration. The return fuel flow in conduit 33 is reducedwith a consequent pressure rise in chamber 26 tending to increase thepressure differential cross orifice 41 as desired, during acceleration.

It is to be noted that upon opening of throttle 52 during accelerationof the engine, the manifold pressure in conduit 49 increases, enablingspring 50 to move valve 46 downward and decrease the restriction atorifice 41. Without provision to the contrary, the pressure in chamber26 would drop momentarily and cause rightward movement of diaphragm 23,with a resulting drop in pressure in chambers 27 and 40 which are incommunication via conduit 54. The momentary low pressure in chamber 27would rob fuel from chamber 40 via conduit 54 and momentarily reduce thefuel pressure in chamber 40. The fuel supply to the engine would thus bereduced at the very time that acceleration was desired. Coughing ormomentary stalling of the engine would result.

By virtue of the conduit 62 connecting pump 17 and the right side ofdiaphragm 72 and in consequence of the leftward movement of orificemember 32 toward valve element 35, the momentary effect of reducing therestriction at orifice 41 during acceleration is minimized. Orificemember 32 is restricted and the return fuel flow therethrough is reducedto cause a momentary pressure rise in chambers 26 and 27 to give theengine a burst of accelerating fuel as desired. After depression ofpiston 60 and the momentary burst of accelerating fuel is supplied, thefuel pressure in chamber 59 and at the right side of diaphragm 75 willleak through restricted bleed orifice 61a to the return fuel line.

It is to be noted further that the structure shown provides for leftwardmovement of orifice member 32 during acceleration with a pump 17 ofminimum fluid displacement. Accordingly the structure illustrated is notonly immediately responsive to operation of the accelerator mechanism6011, but a conventional fuel accelerating pump can be employed for thepump 17. If desired, a major portion of the output from pump 17 can besupplied directly to the engine in accordance with customary practiceand a small portion of the output of pump 17 can be applied to shiftorifice member 32 leftward as described below as in regard to Figure 3.

Also as illustrated in Figure l, the lower chamber 79 of a fluidcontaining pressure regulator or pressure increasing valve housing 80 isconnected by duct 81 with the return flow conduit 33, the housing 80being partitioned by a flexible diaphragm 82 to provide the aforesaidlower chamber 79 and an upper chamber 83. A needle valve element 84secured to diaphragm 82 to move therewith extends upwardly to registerwith a metering orifice 85 which communicates with conduit 44 adjacentits juncture with conduit 43. A biasing springtermined minimumdifferential between the fuel pressure in conduit 43 and the fuelpressure in the return flow conduit 33, as described below.

As is apparent from Figure 1, the pressure in conduit 33 augments theforce of spring 86 urging diaphragm 82 and needle valve 84 upwardly inopposition to the pressure in feed conduit 43 urging diaphragm 82downwardly. Upward or downward movement respectively of valve element 84progressively restricts or opens orifice 85. In the event of a pressureincrease in conduit 33 for any cause, as for example on inclination ofthe vehicle to raise fuel tank 14 with respect to metering orificemember 32, the pressure increase is transmitted to the under side ofdiaphragm 82 to increase the restriction of orifice when the pressure infeed conduit 44 drops below a predetermined minimum value, as forexample when the engine is operating at low load. The pressure in feedduct 43 is thereby increased to increase the pressure in chamber 27 viaconduit 54 and also to increase the pressure in chamber 83 via duct 87connected with feed conduit 43.

The increased pressure in chamber 27 urges diaphragm 23 to the rightbecause of its larger area with respect to the area of diaphragm 24,causing valve element 35 to increase the restriction of metering orifice32. The latter action reduces the pressure in return conduit 33 and alsoin chamber 79. The resulting reduced upward force on diaphragm 82,augmented by the increased pressure in chamber 83, tends to restore theopening of orifice 85 to the extent predetermined by biasing spring 86.Accordingly, any tendency to increase the pressure in return conduit 33results in a corresponding tendency to increase the pressure in chambers26 and 40, so that the pressure differential between conduits 33 and 43will not drop below a predetermined minimum value determined by theforce of spring 86. This structure is particularly important duringlight engine loads when the pressure downstream of port 85 is a minimum.Valve 84 assures a compartively high minimum pressure upstream of port85 and minimizes the tendency of fuel vapor formation during suchconditions in the metering system.

The operation of the speed sensor 15 and load sensor 16 will bedescribed in relation to a static engine operating condition, that isconstant engine speed and load. Under static conditions, the forceexerted on valve element 35 by flyweights 37 equals the force exerted onvalve 35 by the fuel pressure differential across diaphragm 23, wherebyvalve 35 is positioned with respect to orifice member 32 so as tomaintain a pressure differential across orifice 41 determined by enginespeed. In this static condition, the amount of fuel delivered to therosette 42 is constant and is equal to the amount of fuel delivered tothe system by the pump 31 less the amount of fuel being returned to thefuel tank 14 through the return flow of conduit 33.

As throttle valve 52 is moved to a more open position by operation ofthe engine accelerator including linkage 60a, an increase in manifoldpressure is transmitted to the load sensor piston 47 through conduit 49,enabling spring 50 to move piston 47 downwardly and thereby to move theload metering valve 46 to a more open positionwith respect to themetering orifice 41. The pressure diiferenti-al existing across orifice41 and therefore across diaphragm 23 consequently tends to decrease asmore fuel is allowed to flow into chamber 40. To prevent such acondition and to maintain the pressure differential across orifice 41 ata value where the flow of fuel therethrough will satisfy the increasedengine load requirement, the fuel pressure in chamber 26 is increased bymovement of the return flow metering valve 35 closer to orifice member32 in consequence of the increased pressure in chamber 27 whichcommunicates via duct 54 with chamber 40. Thus the return fuel flow inconduit 33 is decreased and the fuel flow to the engine via conduits 43and 44 is increased. Similarly when the engine speed is increased, thefiyweights 37 exert increased force on valve 35 urging the latterrightward to restrict orifice member 32. The result is to decrease thereturn fuel flow in conduit 33 and increase the flow to the engine viaconduits 43 and 44. The converse operation will of course occur in theevent of a reduction in engine load or speed.

Figure 3 shows a modified form of the present invention wherein thepressurized fuel discharged from cylinder 59 upondownward movement ofpiston 60 during acceleration is directed through conduit 62a to theupper chamber 90 of a fluid containing pressure operated check valvehousing 91 which is partitioned by a flexible diaphragm 92 into theaforesaid upper chamber 90 and a lower chamber 93. A shiftable needlevalve element 94 secured to diaphragm 92 to move therewith has a taperedupper end registering with an acceleration orifice 95 to close thelatter. Upon downward movement of valve element 94, chamber 90communicates with chamber 42 via port 95 and duct 44. Needle valve 94 isnormally maintained in the closed position shown by a biasing coilspring 96 under compression between the underside of diaphragm 92 and alower portion of the housing 91. Chamber 93 is in communication withreturn flow conduit 33 via duct 97, whereby excess pressure buildup inchamber 93 is avoided and the return flow in conduit 33 is employed toaugment spring 96 in maintaining valve element 94 in the closedposition. In Figure 3, conduit 62 connects duct 63 with chamber 90instead of directly with cylinder 59 as in Figure 1.

In accordance with the foregoing, when accelerator piston 60 isdepressed to discharge fuel from cylinder 59 during an acceleratingoperation, the first fuel output of pump 17 is directed into chamber 90and thence by conduits 62, 63, and 75' to the right side of diaphragm 72to cause leftward shifting of orifice member 32 as described above.Thereafter upon continued downward movement of piston 60, the fueldischarged from cylinder 59 into cylinder '90 forces diaphragm 92downwardly against the tension of spring 96, thereby causing the valveelement 94 to open orifice 95. Opening of the latter orifice admits theaccelerating fuel into conduit 44 and thence into chamber 42 and to theengine via the various fuel supply conduits 51. Accordingly, a smallportion of the fuel pump discharge is applied to shift orifice member 32and to prevent a momentary pressure drop in chambers 26 and 27, whereasthe primary output of pump 17 discharges directly to the engine asrequired during rapid acceleration. Inasmuch as the fuel discharged frompump 17 is consumed by the engine, the bleed duct 61a of Figure 1 is notessential in Figure 3 because leakage around piston 60 for example willdissipate residual pressure in chamber 90 when port 96 is closed.However, such a duct may be employed if desired. In all other respects,the structure and operation of the mechanism illustrated in Figure 3 isthe same as in Figure 1, so that corresponding parts are numbered thesame in both drawings.

The structure of Figure 3 is advantageous because it is undesirable tomove orifice member 32 too far to the left during acceleration. Toogreat a restriction of orifice member 32 would result in an unbalancingof the fuel metering system and flooding of the engine and fuel wasteduring acceleration. In Figure 1, this problem is made by suitablydetermining the size of the accelerator pump 17 and the resistance tofuel flow in lines 62, 63, and 75. In Figure 3, on the other hand,greater versatility and control is enabled with relaxed productiontolerances. The accelerating fuel pressure in excess of a desired valuedetermined by spring 96 is supplied directly to the engine, so that thetendency to unbalance the metering system, including the relationshipbetween valve 35 and orifice member 32 and the pressure drop acrossorifice 41, is avoided.

It is also to be noted in regard to Figures 1 and 3 that duringdeceleration of the engine and movement of throttle valve 52 toward itsclosed position shown, the accelerator pump piston 60 is raised for thefuel inlet stroke. Fuel then enters cylinder 59 both through duct 57 andthrough conduit 62 from chamber 90. This latter effect reduces thepressure at the right side of diaphragm 72 and enables orifice member 32to move rightward to the limit of its movement illustrated. The fuelpressure. in both chambers 26 and 40, as well as the fuel flow to theengine, is thereby reduced to minimize tmburned fuel in the engineexhaust system during rapid deceleration.

Figure 4 illustrates a structure similar to Figure .3 wherein a plug 100is interposed in conduit 44 between chamber 4 2 and orifice 95. Alsodistinguishing from Figure 3, conduit 62 connects conduit 63 withconduit 44 at a location between the plug 100 and port 95. Accordinglyupon operation of the accelerating pump 17, no fuel pressure is suppliedto conduit 62 until the fuel pump discharge pressure in chamber 99exceeds the predetermined pressure of spring 96. At such a pressure,diaphragm 92 and valve 94 are forced downwardly to open port 95 andconnect the discharge from pump 17 to conduit 62, thereby to shiftorifice member 32 leftward in the manner and for the purpose asexplained above in connection with Figure 1. In this structure, thedischarge from pump 17 is not fed directly to the engine, so that bleedduct 61a is employed to bleed the pressure from chamber 59 after themomentary need for accelerating fuel passes.

I claim:

1. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a port, an adjustable valve seat at said port,a shiftable valve element cooperable with said seat to regulate the fuelflow through said port, valve actuating means responsive to an operatingcondition of said engine for shifting said valve element, and meansresponsive to an operating condition of said engine during accelerationfor adjusting the position of said valve seat to augment operation ofsaid metering means tending to increase the fuel flow to said engine.

2. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a port, an adjustable valve seat at said port,a shiftable valve element cooperable with said seat to regulate the fuelflow through said port, valve actuating means responsive to an operatingcondition of said engine for shifting said valve element, and meansresponsive to an operating condition of said engine during'accelerationfor adjusting said valve seat.

3. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a fuel chamber in said conduit means having aport, an adjustable valve seat at said port, a shiftable valve elementcooperable with said seat to regulate the fuel flow through said port, amovable partition separating said chamber into two parts with said portbeing in one thereof, said partition being shiftable in response tochanges in the fuel pressure differential at its opposite sides andbeing operatively connected with said valve element to shift the same,valve actuating means responsive to an operating condition of saidengine and being cooperable with said valve element for shifting thesame, and means responsive to an operating condition of said engineduring acceleration for adjusting the position of said valve 9 seat toaugment operation of said metering means tending to increase the fuelflow to said engine.

4. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a fuel chamber in said conduit means having aport, an adjustable valve seat at said port, a shiftable valve elementcooperable with said seat to regulate the fuel flow through said port, amovable partition separating said chamber into two parts with said portbeing in one thereof, said partition being shiftable in response tochanges in the fuel pressure differential at its opposite sides andbeing operatively connected with said valve element to shift the same,valve actuating means responsive to an operating condition of saidengine and being cooperable with said valve element for shifting thesame, fluid pressure actuated means operatively connected with said seatto adjust the same, fluid pumping means operable during acceleration ofsaid engine to supply pressurized fluid to said pressure actuated meansto adjust said seat to augment operation of said metering means tendingto increase the fuel flow to said engine.

5. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a fuel chamber in said conduit means having aport, an adjustable valve seat at said port, a shiftable valve elementcooperable with said seat to regulate the fuel flow through said port, amovable partition separating said chamber into two parts with said portbeing in one thereof, said partition being shiftable in response tochanges in the fuel pressure differential at its opposite sides andbeing operatively connected with said valve element to shift the same,valve actuating means responsive to an operating condition of saidengine and being cooperable with said valve element for shifting thesame, a flexible diaphragm connecting said seat and chamber and definingin part a second chamber separate from the first named chamber, saiddiaphragm being shiftable in response to fluid pressure in said secondchamber to adjust the position of said seat, and fluid pumping meansselectively operable to supply pressurized fluid to said second chamber.

6. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a fuel chamber in said conduit means having aport, an adjust-able valve seat at said port, a shiftable valve elementcooperable with said seat to regulate the fuel flow through said port, amovable partition separating said chamber into two parts with said portbeing in one thereof, said partition being shiftable in response tochanges in the fuel pressure differential at its opposite sides andbeing operatively connected with said valve element to shift the same,valve actuating means responsive .to an operating condition of saidengine and being cooperable With said valve element for shifting thesame, fluid pressure actuated means operatively connected with said seatto adjust the same, fluid pumping means operable during acceleration ofsaid engine, a conduit connecting said pumping and pressure actuatedmeans to deliver pressurized fluid thereto to actuate the latter andadjust said seat upon operation of said pumping means, pressureresponsive valve means normally closing said conduit between saidpumping and pressure actuated means, said valve means being responsiveto a predetermined fluid pressure exerted by said pumping means to opensaid conduit between said pumping and pressure actuated means.

7. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a fuel chamber in said conduit means having aport, an adjustable valve seat at said port, a shiftable valve elementcooperable with said seat to regulate the fuel flow through said port, amovable partition separating said chamber into two parts with said portbeing in one thereof, said partition being shiftable in response tochanges in the fuel pressure diflerential at its opposite sides andbeing operatively connected with said valve element to shift the same,valve actuating means responsive to an operating condition of saidengine and being cooperable with said valve element for shifting thesame, pressure actuated means operatively connected with said seat toadjust the same, acceleration fuel pumping means selectively operable tosupply pressurized accelerating fuel to said engine, duct meansconnecting said pumping and pressure actuated means to deliverpressurized accelerating fuel thereto to actuate the latter and adjustsaid seat to augment operation of said metering means tending toincrease fuel flow to said engine upon operation of said pumping means.

8. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a fuel chamber in said conduit means having aport, an adjustable valve seat at said port, a shiftable valve elementcooperable with said seat to regulate the fuel flow through said port, amovable partition separating said chamber into two parts With said portbeing in one thereof, said partition being shiftable in response tochanges in the fuel pressure differential at its opposite sides andbeing operatively connected with said valve element to shift the same,valve actuating means responsive to an operating condition of saidengine and being cooper-able with said valve element for shifting thesame, pressure actuated means operatively connected with said seat toadjust the same, acceleration fuel pumping means selectively operable tosupply pressurized accelerating fuel to said engine, duct meansconnecting said pumping and pressure actuated means to deliverpressurized accelerating fuel thereto to actuate the latter and adjustsaid seat to augument operation of said metering means tending toincrease fuel flow to said engine upon operation of said pumping means,pressure responsive valve means normally closing the fluid connectionsof said pumping means with said pressure actuated means and engine, saidvalve means being responsive to a predetermined fuel pressure exerted bysaid pumping means to open said connections.

9. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a fuel chamber in said conduit means having aport, an adjustable valve seat at said port, a shiftable valve elementcooperable with said seat to regulate the fuel flow through said port, amovable partition separating said chamber into two parts with said portbeing in one thereof, said partition being shiftable in response tochanges in the fuel pressure differential at its opposite sides andbeing operatively connected with said valve element to shift the same,valve actuating means responsive to an operating condition of saidengine and being cooperable with said valve element for shifting thesame, a flexible diaphragm connecting said seat and chamber and definingin part a second chamber sepamate from the first named chamber, saiddiaphragm being shiftable in response to fluid pressure in said secondchamber to adjust the position of said seat, acceleration fuel pumpingmeans selectively operable to supply pressurized accelerating fuel tosaid engine, and duct means connecting said pumping means and secondchamber to discharge pressurized accelerating fuel thereto uponoperation of said pumping means.

10. In a fuel system for an internal combustion engine,

fuel conduit means for supplying said engine with fuel, fuel meteringmeans for regulating the fuel flow in said conduit means to said engine,said fuel metering means including a fuel chamber in said conduit meanshaving a port, an adjustable valve seat at said port, a shiftable valveelement cooperable with said seat ot regulate the fiuel flow throughsaid port, a movable partition separating said chamber into two partswith said port being in one thereof, said partition being shiftable inresponse to changes in the fuel pressure differential at its oppositesides and being operatively connected with said valve element to shiftthe same, valve actuating means responsive to an operating condition ofsaid engine and being cooperab-le with said valve element for shiftingthe same, a flexible diaphragm connecting said seat and chamber anddefining in part a second chamber separate from the first named chamber,said diaphragm being shiftable in response to fluid pressure in saidsecond chamber to adjust the position of said seat, acceleration fuelpumping means selectively operable to supply pressurized acceleratingfuel to said engine, duct means connecting said pumping means and secondchamber to discharge pressurized accelerating fuel thereto uponoperation of said pumping means, pressure responsive valve meansnormally closing the fluid connections of said pumping means with saidengine and second chamber, said valve means being responsive to apredetermined fuel pressure exerted by said pumping means to open saidconnections.

11. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a port in said conduit means, an adjustahlevalve seat at said port, a shiftable valve element cooperable with saidseat to regulate the fuel flow through said port, valve actuating meansresponsive to an operating condition of said engine for shifting, saidvalve element, a pressure actuated member operably connected Wtih saidvalve seat for adjusting the latter, fluid pressure exerting meansresponsive to an operating condition of said engine during accelerationfor applying fluid pressure to said member to actuate the latter, andmeans shileding said member from the fuel pressure in said conduit meansat the high pressure side of said port.

12. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a port in said conduit means, an adjustablevalve seat at said port, a shiftable valve element cooperable with saidseat to regulate the fuel flow through said port, valve actuating meansresponsive to an operating condition of said engine for shifting saidvalve element, a pressure actuated member operably connected with saidvalve seat for adjusting the latter, fluid pres sure exerting meansresponsive to an operating condition of said engine during accelerationfor applying fluid pressure to one side of said member to actuate thelatter to adjust said valve seat to augurnent operation of said meteringmeans tending to increase the fuel flow to said engine, means shieldingsaid member from the fuel pressure in said conduit means at the highpressure side of said port, and means applying the fuel pressure in saidconduit means at the low pressure side of said port to said member inopposition to said one side.

13. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a port in said conduit means comprising anannular valve seat member slidable axially in a relatively fixed portionof said conduit means, a flexible annular diaphragm around said seatmember, the inner and outer peripheries of said annular diaphragm beingsecured to said member and fixed portion respectively in fluid sealingengagement therewith, a shiftable valve element cooperable with saidseat member to regulate the fuel flow through said port, valve actuatingmeans responsive to an operating condition of said engine for shiftingsaid valve element, fluid pressure exerting means responsive to anoperating condition of said engine during acceleration for applyingfluid pressure to one side of said diaphragm to actuate the latter andadjust said seat member to augment operation of said metering meanstending to increase the fuel flow to said engine, and means for applyinga comparatively low fluid pressure to the side of said diaphragmopposite said one side.

l4.. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a port in said conduit means comprising anannular valve seat member slidable axially in a relatively med portionof said conduit means, a flexible annular diaphragm around said seatmember, the inner and outer peripheries of said annular diaphragm beingsecured to said member and fixed portion respectively in fluid sealingengagement therewith, a shiftable valve element cooperable with saidseat member to regulate the fuel 'flow through said port, valveactuating means responsive to an operating condition of said engine forshifting said valve element, fluid pressure exerting means responsive toan operating condition of said engine during acceleration for applyingfluid pressure to one side of said diaphragm to actuate the latter andadjust said seat member to augment operation of said metering meanstending to increase the fuel flow to said engine, and means connectingthe side of said diaphragm opposite said one side to the fuel pressureof said conduit means at the low pressure side of said port.

15. ,In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a port in said conduit means comprising anannular valve seat member slidable axially in a relatively fixed portionof said conduit means, a flexible annular diaphragm around said seatmember, the inner and router peripheries of said annular diaphragm beingsecured to said member and fixed portion respectively in fluid sealingengagement therewith, a shiftable valve element cooperable with saidseat member to regulate the fuel flow through said port, valve actuatingmeans responsive to an operating condition of said engine for shiftingsaid valve element, acceleration fuel pumping means selectively operableto supply pressurized fuel to said engine, means for applying thepressure of said pressurized fuel to one side of said diaphragm toactuate the latter and adjust said seat member to augment operation ofsaid metering means tending to increase the fuel flow to said engine,and means for applying a comparatively low fluid pressure to the side ofsaid diaphragm opposite said one side.

16. In a fuel system for an internal combustion engine, fuel conduitmeans for supplying said engine with fuel, fuel metering means forregulating the fuel flow in said conduit means to said engine, said fuelmetering means including a port in said conduit means comprising anannular valve seat member slidable axially in a relatively fixed portionof said conduit means, a flexible annular diaphragm around said seatmember, the inner and outer peripheries of said annular diaphragm beingsecured to said member and fixed portion respectively in fluid sealingengagement therewith, a shiftable valve element cooperable with saidseat member to regulate the fuel flow through said port, valve actuatingmeans 13 responsive to an operating condition of said engine forshifting said valve element, acceleration fuel pumping means selectivelyoperable to supply pressurized fuel to said engine, meansfor applyingthe pressure of said pressurized fuel to one side of said diaphragm toactuate 5 the latter and adjust said seat member to augment opera- 14tion of said metering means tending to increase the fuel flow to saidengine, and means connecting the side of said diaphragm opposite saidone side to the fuel pressure of said conduit means at the low pressureside of said port.

No references cited.

UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent No.2,958,320 November l, 1963 Thomas M. Ball It is hereby certified thaterror appears in the above numbered patent requiring correction and thatthe said Letters Patent should read as corrected below.

Column 5, line 25, for "cross read across column 10, line 41, for"augument" read augment coiumn 11, line 7, for "fiuel" read fuel line41, for wtlh" read with line 45, for "shileding" read shielding line 62,for "augument" read augment Signed and sealed this 25th day of April1961.,

(SEAL) Attest- ERNEST W, SWIDER DAVID L, LADD Attesting Officer I ICOHIIIHSSIODCI of Patents

